import {readdirSync, readFileSync} from 'fs';

let idPerfix = '';
const iconNames: string[] = [];
const svgTitle = /<svg([^>+].*?)>/;
const clearHeightWidth = /(width|height)="([^>+].*?)"/g;
const hasViewBox = /(viewBox="[^>+].*?")/g;
const clearReturn = /(\r)|(\n)/g;
// 清理 svg 的 fill
const clearFill = /(fill="[^>+].*?")/g;

function findSvgFile(dir: string): string[] {
    const svgRes = [] as any;
    const dirents = readdirSync(dir, {
        withFileTypes: true,
    });
    for (const dirent of dirents) {
        iconNames.push(`${idPerfix}-${dirent.name.replace('.svg', '')}`);
        if (dirent.isDirectory()) {
            svgRes.push(...findSvgFile(dir + dirent.name + '/'));
        } else {
            const svg = readFileSync(dir + dirent.name)
                .toString()
                .replace(clearReturn, '')
                .replace(clearFill, 'fill=""')
                .replace(svgTitle, ($1, $2) => {
                    let width = 0;
                    let height = 0;
                    let content = $2.replace(clearHeightWidth, (s1: string, s2: string, s3: number) => {
                        if (s2 === 'width') {
                            width = s3;
                        } else if (s2 === 'height') {
                            height = s3;
                        }
                        return '';
                    });
                    if (!hasViewBox.test($2)) {
                        content += `viewBox="0 0 ${width} ${height}"`;
                    }
                    return `<symbol id="${idPerfix}-${dirent.name.replace('.svg', '')}" ${content}>`;
                })
                .replace('</svg>', '</symbol>');
            svgRes.push(svg);
        }
    }
    return svgRes;
}

export const svgBuilder = (path: string, perfix = 'local') => {
    if (path === '') return;
    idPerfix = perfix;
    const res = findSvgFile(path);
    return {
        name: 'svg-transform',
        transformIndexHtml(html: string) {
            /* eslint-disable */
            return html.replace(
                '<body>',
                `
                <body>
                <svg id="local-icon" data-icon-name="${iconNames.join(
                    ','
                )}" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" style="position: absolute; width: 0; height: 0">
                ${res.join('')}
                </svg>
                `
            );
            /* eslint-enable */
        },
    };
};
